Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan (Mu.T., M.I., S.N., A.W., Y.O., T.D., K.Y., J.K., M.K.); Laboratory of Vaccine Materials and Laboratory of Gut Environmental System, National Institute of Biomedical Innovation, Osaka, Japan (Mu.T., H.S., J.K.); Division of Biological Chemistry and Biologicals, National Institutes of Health Sciences, Tokyo, Japan (Mi.T.); Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan (M.F.); Graduate School of Medicine and Graduate School of Dentistry, Osaka University, Osaka, Japan (J.K.); Division of Mucosal Immunology, Department of Microbiology and Immunology and International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan (J.K.); and Department of Microbiology and Immunology, Kobe University Graduate School of Medicine, Hyogo, Japan (J.K.)